I own both lenses, and the 85L is better in all of those categories you just mentioned (IQ, sharpness, contrast, and color rendering), although the 50L does focus much more quickly. I keep the 50L around for the shorter reach. I wouldn't recommend the 85L for fast-moving subjects, but it's churned out some amazing photographs for me.

50L is much faster at focusing, but the copy I had was also rather inconsistent. Sometimes front focused, sometimes back focused. Could've just been my copy though. The 85 is slower and heavier, but is much sharper than the 50 when shooting wide open at f/1.2. The 50L looks sharp if you're not pixel peeping. In the sweet spot, crop or zoom in, and everything has a bit of a soft blur around it. Stopped down to f/2 though, it's razor sharp across the board with lovely color and contrast. I sold my 50L and kept my 85L, but that's just me

There is pretty much nothing to add. The 85 1.2 II is way slower in focussing than the 50 1.2L, but the 50 1.4 is even faster, so i wouldn't say the 50 1.2 is a quick focussing lens. When it comes to sharpness wide open than the 85 is wayyyy sharper. Both have little issues with CA's at 1.2 in high contrast szenarios but thats normal for such huge glasses i'd say. Another thing is, that the full electronic focus of the 85 is kind of weird. You have to switch to "manual focus" if you want to focus manually, there is no override in AF mode. The focus ring is more like a "sensor" that gives the information to the focus motor. This doesen't work when AF is enabled. The focus ring is also wayyy to smoth, it turns like its a spinning wheel. I like the "mechanical" way of the 50 much much better. Another thing is that the 85 is not weather sealed and the front element extends (and sticks out) a lot when focussing (the front element of the 50 also moves, but it dosent stick out of the lens at any focussing distance). If I could only afford one it, would defenitly be the 85 1.2 II because of its simply the best portrait lens out there (if you are kind of close to your subject, sometimes I take it also for whole body portraits). If you want more "distance" to your model and en even tighter field of view then go for the 135L.

Very true, the focus-by-wire takes some getting used to. I'm actually quite fond of the almost frictionless spin of the 85's focus wheel, personally. For video work, it allows you to do big focus racks without having to manhandle the lens much - just roll the side of your finger across the barrel. Whereas you have to grip other lenses more firmly, often resulting in microjitters. So, for video, I love the light touch of the 85's wheel. For stills... eh, I'm usually using AF anyway.

These are two of my favorite lenses, the 85L definitely has the edge in sharpness and bokeh but I feel like when the 50L is on point that the shots match very well between the two lenses. Not to say that they are equal, they just have similar qualities. The 50L is the better walk around lens of course, but if you're into portraits nothing beats the 85L. Like someone else said though, the 135L is an excellent lens and 1/2 the price of the 85L.

I had the 85LI and sold it for the 50L. This focal length and speed of focus was worth it. The 85LI isn't much slower than the 85LII and optically it is the same pretty much. Still the 85 is magic. I didn't like shooting that focal length as much though. I get more value out of the 50L and the bokeh pretty much looks close to the same as the 85L.My shooting style would like the 85L again but i won't sacrifice going without a weather seal. The 85L and 35L are the only lenses i know of that don't have the seal. I won't pay this amount without it.

It depends on what you will use it for, just to add to the above, which I, for the most part, agree with. The 85 is very heavy compared. I have them both and for sharpness I too think the 85 is better, this has alot to do with the lack of floating elements in the 50.

This being said, I use the 50 almost every single day and the 85 for maybe 10% of my images. Contrast and color I like the 50 better and imo the 50 handles the best on all Canon bodies by far.